PROJECT SUMMARY/ABSTRACT The aim of this proposal is to replace the currently dysfunctional, unsupported and discontinued ?Varian? console (due to termination of Varian as a company) on a unique 16.4 Tesla/26 cm bore Instrument dedicated to small to medium size animal model studies at the Center for Magnetic Resonance Research (CMRR). Currently CMRR possesses a unique 16.4T/26 cm horizontal bore instrument which was funded by an $2M HEI grant in 2007/2008 and substantial matching funds (~ $10M) from the University of Minnesota in order to expand the boundaries of magnetic resonance (MR) methodologies and their applications in biomedical research using small to medium-sized animals (e.g. rodents to cat). This unique NMR instrument is the highest magnetic field available for animal model studies in the U.S.A. Only one instrument (located in Neurospin in France) operating at 17.2T exceeds it in magnetic field strength for small to medium size animal model studies (a 21 Tesla vertical bore system large enough for mouse and rat studies but not medium size animals exists in the Magnet lab in the USA). CMRR?s 16.4T system was meant to play a crucial role in a large number of projects on animal models conducted within our past Biotechnology Research Center (BTRC, P41 EB015894) and the NINDS Institutional Center Core Grants to Support Neuroscience Research (P30 NS076408), as well as multiple large NIH funded projects supported by R01 and other grant mechanisms. It is still slated for a critical role in our recently funded BTRC P41 EB02706, and competitively renewed P30 grants (2P30 NS076408) both of which support a multitude of projects, as well as in numerous currently funded R01 and U01 grants. However, instrument has been and currently still is dysfunctional for 1H studies, and has also reached its limits of its viability for all other nuclei due the disappearance of the console manufacturer Varian. This instrument was purchased from Varian Inc. However, shortly after that instrument was established, Varian was purchased by Agilent Technologies in 2010. Because of the transition, problems with 1H nuclei remained unsolved though the instrument worked well for less demanding low gamma nuclei. In 2013 Agilent decided to terminate the MR Imaging business completely and approximately a year later closed down all NMR activities, thus leaving essentially all Varian users, including us, in a very difficult position. Several problems on the instrument after its delivery (e.g. gradient driver instabilities, SNR losses in 1H frequency) remained unresolved as many Varian engineers were laid off and a commitment and the ability to fix these problems in Agilent vanished. Already many Varian users migrated to the consoles provided mainly by Bruker. Therefore, we are pursuing in this application what must inevitably happen due to the disappearance of Varian as a manufacturer and service organization; namely replacing it with an integrated and supported console from Bruker.